
in 
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1868 



LIBRARY OF CONGRESS. 



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UNITED STATES OF AMEEICA. 



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ZWICKER'S 
INSTTRUCTOR, 

THE 

ONLY PRACTICAL WORK PUBLISHED, 

FOR 

MACHIKISTS, FIREMEH 



K Steam EngineePs. 

BY PHILIP HENRY ZWICKER, 

Practicai, Engineer and Machinist. 



ST. LOUIS, MO. 






V-sJ 



Entered according to Act of Congress, 

in the year 1888, 

By Philip Henry Zwicker, 

In the office of the Librarian of Congress at Washington 

All rights of Translation reserved. 






PREFACE. 

• 

In the following pages I have explained 
the practical points of the Steam Boiler, 
Engine, Pump, Indicator, Safety Yalve, U. 
S. Standard Rules and the gearing of a lathe 
to cut any size and kind of thread, in a clear 
and concise manner, so as to be easily under- 
stood by men whose education is limited. 

I have also appended important tables so 
simple that they can be readily understood. 
Almost all calculations connected with the 
use of steam can be calculated, providing the 
first four rules of the arithmetic are known 
viz : Addition, multiplication, subtraction 
and division. These hints and examples are 
intended to show how many practical im- 
provements can be made by engineers, fire- 
men and machinists. 

The importance of this book is, to keep 
engineers informed of their duty in regard to 
the safety valve, engine, boiler, pump and 



IV 

indicator. An engineer of plain education, 
studying this book, will find that it is simple 
and easily learned; also the only book pub- 
lished explaining these things clearly and to 
the point. 

Every engineer, fireman and machinist 
ought to know perfectly well, without the ne- 
cessity of any elaborate calculations, theor- 
izing, or calling in the services of some expert 
(engineer) to tell him clearly what would 
occur if he should overload his engine, 
boiler or any machinery under his charge. 

I trust this book will be of service to those 
who intend to follow steam engineering, as 
well as tci all whose business make it necessary 
to use steam. 

PHILIP H. ZWICKEK, 

AUTHOR. 



ZWICKER'S 

i2srsm?,xjCTionsrs 

QUESTIONS AND ANSWERS 

FOR 

Machinists, Firemen and Steam Engineers. 



Question. Are you a machinist ? 

Answer. Yes or no. 

Q. Have you worked at finishing ? 

A. Yes or no. 

Q. What kind of boilers are there ? 

A. There are diiferent kinds; such as 
flue, tubular, hanging-fire box, upright and 
various other kinds, but the above named are 
most in use. 

Q. Of what is a boiler composed and 
made ? 

A. A steam boiler is made out of steel or 
iron plates, the most in use is f , J and 1^3 inch 



— 6 — 

thick, and ranging from 45,000 to 85,000 lbs. 
tensile strength; these plates are run through 
a rolhng machine and rolled in a circle, then 
riveted together, generally with two rows of 
rivets, because the strain is greater sidewise 
than endwise, the seams around the boiler are 
single rivited because the strain is not so 
great; the boiler is braced by different kinds 
of braces, such as crow foot, longitudinal, 
dome, side braces, etc. The eye is riveted 
to the head of the boiler, which head is 
generally made of f inch plate, the other eye 
is riveted to the side, top or dome of boiler; 
and the brace and eye are put together by 
bolts vdth a split key to keep the bolt in place. 

Q. How should a brace fit ? 

A. It should fit tight, for if it were loose 
it would be of no account. 

Q. If you found a brace loose, what 
would you do and how would you tighten it 'I 

A. By taking the brace out, heat it in 
the center, then upset it by jumping it end- 
wise on a block of wood until it is the proper 
length. 

Q. Why is a boiler braced ? 



A. For strength. 

Q. What is a stay-bolt '( 

A. A stay-bolt is a screw bolt, put 
through an outside and into an inside sheet, 
so as to hold them that they may not spread 
or collapse, such as a fire-box sheet and an 
outside shell, they are put together with 
stay-bolts so as to allow a water space 
between the two sheets. 

Q. How is a stay-bolt made and put in ? 

A. They are made with one continuous 
thread, and screwed through the outside, then 
through the space between, then through 
the fire-box sheet and allowed to stick 
through 1^6 of an inch, so they can be 
riveted over each end to act as a brace, the 
space between the two sheets is called a water 
space. 

Q. ^^at is meant by corrosion ? 

A. It means wasting away of the iron of 
boiler plates by pitting, grooving, etc. There 
is internal and external corrosion ; the acids 
and minerals in the water liberated by the 
heat, attack the boiler internally, and the 
sulpliur which comes out of the coal has a 



— 8 — 

strong attachment fot* the iron, and that 
attacks the outside. 

Q. How would you find the water level 
when your boiler is foaming ? 

A. The proper way would be to shut 
down the engine and all valves connected 
with the boiler, cover fire with ashes, close 
the damper, then the water will quiet down, 
and the level of the water easily found. An 
engineer should know when lighting a fresh 
fire, never to force it, but let it heat gradually, 
so that all parts expand as near equal as 
possible ; good judgment is needed. Boilers 
and steam gauges should be tested at least 
once a year. 

Q. Where would you put a steam gauge ? 

A. Sometimes on top of the boiler, and 
in some cases on the steam drum. It must 
always be tapped into the steam part of the 
boiler, the shorter the pipe the better. The 
steam gauge and safety valve should corres- 
pond. 

Q. Why is a pet cock put under the 
steam gauge ? 

A. To drain the pipe in cold weather. 



Q. What kind of a steam gauge have you 
got? 

A. A spring gauge. 

Q. What is a steam gauge for ? 

A. To indicate the pressure in pounds per 
square inch in the boiler. 

Q. Does the steam gauge get out of order 'i 

A. Yes. 

Q. If the steam gauge was out of order 
what would you be governed by ? 

A. By the safety valve. 

Q. How would you know that it was in 
order ? 

A. By raising the lever two or three 
times to see that the valve is not stuck. 

Q. What is a safety valve for ? 

A. It is intended to release the boiler and 
prevent explosions from over-pressure. 

Q. How large should the safety valve be 
in proportion to the boiler, and grate surface ? 

A. The safety valve should be |- square 
inch to each square foot of grate surface, 
which will make it large enough to relieve 
the boiler of all steam generated over which 
the safety valve is set. 



— 10 — 

Q, What is the best, gauge cocks or glass 
gauges, and what would you be governed by 'i 

A. Gauge cocks, because glass gauges are 
liable to get stopped with mud, and not give 
a true level of the water, but they are a very 
handy thing ; they should be blown out four 
or five times a day, so as to keep them free 
from clogging up. 

Q. What would you do in case a glass 
should happen to break ? 

A. First close the water valve to prevent 
the escape of water, close the steam valve, 
insert a new glass, then turn on the steam 
valve first, the water valve next, then close 
the pet cock at the bottom and everything 
will be all right. 

Q. What is the best way to clean a glass 
gauge inside ? 

A. The best way, is to take a small piece 
of waste and tie it to a strong thin stick, 
saturate the waste with soap or acetic acid, 
pass down inside of the glass, then blow 
through with steam and the glass will be clean 
as new. Never touch the inside of a glass 
water gauge with wire, if you do, it will 



— 11 — 

crack. The best glasses are the Scotch brand, 
called Eureka. 

Q. If your gauge cock, or a small pipe in 
the large steam pipe, should happen to get 
broken off, what would you do ? 

A. Make a hard- wood plug and drive it 
in with a heavy hammer, then leave it so 
until it could be repaired, by cutting out the 
old piece, retapping and putting in another 
pipe or gauge cock, whichever the case 
may be. 

Q. What clearance should a boiler have ? 

A. It should have from 3 to 4 inches at 
the fire line, and from 5 to 7 inches between 
the shell and bridge wall; a boiler should 
have from 2 to 3 bridge walls so the fire will 
hug the boiler; it also makes the coal burn 
cleaner and steams easier. The first bridge 
wall should be on the back end of the grate 
bars, and the others about 3 to 5 feet apart, 
according to the length of the boiler. Wliere 
the smoke returns through the flues, it should 
be about h larger than the area of flues or 
tubes combined, bridge walls should lean 
toward the back. 



— 12 — 

Q. How should a boiler rest and what on ? 

A. The front end of the boiler should 
rest on the fire front, and the back end gene- 
rally rests on a cast iron leg or two rollers, to 
allow the boiler to expand equally. The 
mud drum should always hang free under all 
circumstances. Engineers should be careful 
in starting or stopping an engine with a high 
pressure of steam, because the rent in giving 
the steam in starting, and the sudden 
check in stopping, may cause such a pres- 
sure as to rupture the boiler. Engineers 
should see that their draft is not choked by 
ashes under the boiler, and that the outside 
of the boiler and inside of flues are kept clean, 
then they will have no trouble in keeping 
up steam. 

Q. In case the throttle valve snould be- 
come loose from the stem and prevent the 
steam from entering the valve chest, what 
would you do ? 

A. Close the valve next to the boiler, if 
there was one ; if not, let the boiler cool 
down, then take the valve out and repair it. 

Q. What different strains has a boiler? 



— 13 — 

A. To the flues or tubes it has a crush, 
ing strain, to the shell a tearing strain. 

Q. What causes boiler explosions ? 

A. There are various causes, such as low 
water, over-pressure of steam, bad safety 
valve, foaming boilers and burnt sheets. 

Q. Why would a foaming boiler cause 
an explosion? 

A. It generally raises the water from the 
heated sheets. They become hot ; the water 
falling back on them they crack, and some- 
times cause an explosion. A blistered sheet or 
a scaly boiler will also cause an explosion, by 
allowing the sheets to became burnt and 
weakened ; also, an untrue steam gauge is 
very bad. 

Q. What are the worst explosions ? 

A. The worst explosions are caused by 
high pressure and plenty of water ; low 
water allows the iron to burn and crack, 
which weakens it, and when the cold water 
touches it, it does not take so much to burst. 

Q. How would you know if your boiler 
had bhstered sheets or was rotten ? 

A. By the hammer test ; by taldng a 



14 



small hammer and going inside and outside 
of the boiler and seeing if it is all right by 
sounding it. 

Q. How would you know by sound ? 

A. By the different sounds it has ; if it 
rings and sounds solid it is all right ; but if 
it sounds dead, hollow or blunt, there is 
something wrong. 

Q. Would you strike the iron hard ? 

A. Yes, pretty hard. 

Do not hesitate to have a boiler insured, 
as insurance is generally accompanied by 
hammer test and intelligent inspection, which 
guarantees safety to the engineer, owner or 
steam user. 

Do not reject the advice or suggestions of 
intelligent boiler inspectors, as their expe- 
rience enables them to discriminate in cases 
which never come under the observation of 
men who do not follow inspection as a busi- 
ness. 

Q. If you wished to put a patch on a 
boiler, what kind would you put on ? 

A. A hard patch ; it is reliable and safe. 

Q. Why not put on a soft patch ? 



— 15 — 

A. Because they are not reliable and are 
dangerous. 

Q. What is the difference between a hard 
and soft patch ? 

A. A hard patch is a patch where the 
piece is cut out of the boiler and rivet holes 
are drilled or punched through, then the 
patch is riveted on, chipped, corked and 
made water and steam tight. 

Q. What is a soft patch ? 

A. A soft patch is put over the plate that 
needs patching, and put on with f or f inch 
countersunk screw bolts, and a mixture of 
red lead and iron borings to put between tlie 
patch and boiler ; the piece of sheet in the 
boiler is not cut out for a soft patch as in a 
hard patch, consequently the patch is burnt, 
as the water in the boiler can not come in 
contact with the patch. 

Q. What is the best, drilled or punched 
holes ? 

A. Drilled holes are the best ? 

Q. Why? 

A. Because the fiber of the iron is not 
disturbed as in punching ; in drilling, the 



~ 16 — 

iron is cut out regular ; in punching, it is 
forced out at once. 

Q. What should be the proper rivets for 
certain sized sheets, and how far apart ? 

A. The rivets should be f and f inch di- 
ameter, and li to If inches apart. 

Q. Before shutting down at night, what 
would you do ? 

A. Pull out the fire, pump up to the 
third gauge and close the glass gauge cocks, 
so that in case the glass should happen to get 
broken during the night, the water could not 
escape. 

Q. What would you do the first thing in 
the morning on entering the fire-room? 

A. See how much water was in the boiler 
by trying the gauge cocks, open the glass 
gauge valves, and start the fire to raise 
steam. 

Q. Why do you try the gauge cocks, and 
not trust to the glass gauge ? 

A. Because the water pipe connecting the 
glass gauge with the boiler is liable to become 
stopped up with mud, consequently the glass 
would not show a true level of water. The 



— 17 — 

glass gauge should be l)lown out five or six 
times a day, to insure safety, but never de- 
pend on the glass alone. 

Q. If you found too much water in the 
boiler during the day, what would you do ? 

A. Open the blow-off valve and let out 
water to the second gauge. An engineer 
should be very careful when blowing out 
water when he has a hot fire in the boiler fur- 
nace, as the water leaves very fast, and may 
blow out too much ; good judgment should 
be used. 

Q. How would you clean the flues or 
tubes of a boiler ? 

A. By either blowing steani through 
them or using a flue- cleaning brush. 

Qo How are flues or tubes cleaned with steam? 

A. Some boilers have an 1|- inch pipe with 
a valve attached, also branch pipes of smaller 
dimensions, leading fi'om the 1^ inch into the 
back end and into the flues ; others have a 
hose attached to the front end leading from 
the steam drum, so flues or tubes can be 
blown out from front end. (Cleaning by 

BRUSH IS BEST.) 



— 18 — 

Q. How often would you clean out the 
flues, and when ? 

A. Once a day, and in the afternoon. 
Sometimes in the morning after raising steam. 

Q. How would you clean a boiler ? 

A. First see that no fire is under the 
boiler, then let out all the water through the 
blow-off valve, take out the man, hand, and 
mud-drum plates ; then take a short-handle 
broom, a candle or torch, a small hand-pick, 
a scraper made out of an old file flattened on 
the end and bent to suit, also a half-inch 
square iron twisted link chain, about 3 feet 
long, with a ring at each end to answer for a 
handle ; place chain around the flue and work 
the chain to get the scale ofl' the bottom of 
the flues ; use the pick and scraper to pick 
and scrape off all that can be seen on top of 
flues and the bottom and sides of shell ; then 
wash out into the mud-drum ; clean out and 
put in the mud-drum and hand-hole plates ; 
fill up to top of flues ; then put in man-hole 
plate, and fill up to second gauge ready for 
raising steam. 

Q. Could a boiler not be blown out ? 



— 19 — 

A. Yes. 

Q. How much pressure would you allow ? 

A. About 10 or 20 pounds. 

Q. Why not more pressure ? 

A. Because the heat would be so great 
that the expansion and contraction would not 
be equal ; consequently, the boiler seams 
would probably leak and the boiler l^e in- 
jured. 

Q. What benefit is gained by letting 
water stay in the boiler until you are ready 
to clean out ? 

A. The mud is kept soft and the scale is 
not caked to the bottom ; also, the seams and 
boiler are not injured by unequal expansion 
and contraction. 

Q. How should a man and hand-hole 
plate be taken out and put in ? 

A. They should be marked with a chisel 
at the top, also the boiler at man-hole and 
hand-hole, whichever it might be, and they 
should be put in the same way they came 
out. 

Q. How would you gasket man-hole or 
hand-hole plates ? 



-20 — 

A. With pure lead rings ; some use sheet 
rubber. 

Q. Why are man-hole and hand-hole 
plates made oblong instead of round ? 

A. Because if they were round they could 
not be taken out, and a man could not easily 
enter the boiler. 

Q. When filling a boiler with cold water 
and raising steam, what should be done ? 

A. A valve should be left open. 

Q. Why? 

A. Because a boiler fills easier and quick- 
er, and in raising steam the cold air is let out, 
which allows equal expansion, as cold air pre- 
vents equal expansion. 

Q. How would you set a boiler? 

A.- By using a spirit level across and 
along the flues, allowing the end furthest 
from the gauge cocks J inch lower for every 
10 feet in length. 

Q. Why ? 

A. Because when there is water in the 
gauge cocks, there will surely be water in the 
other end. 

Q. How many gauge cocks has a boiler ? 



— 21 — 

A. Generally three. 

Q. Where is the first ? 

A. Two inches above the flues, and the 
rest two inches apart. 

Q. Where is the water hne ? 

A. First gauge. 

Q. Where would you carry water when 
running ? 

A. Second gauge. 

Q Where would you carry water ^hen 
shutting down at night ? 

A. Third gauge. 

Q. Why? 

A. To allow for evaporation, leakage and 
condensation. 

Q. Where is the fire line of a boiler ? 

A. In line or little below first gauge. 

Q. When you open a boiler and look in, 
where do the scales form and lay thickest ? 

A. Over the fire-plates and around the 
mud-drum leg or blow-oif pipe. 

Q. Why ? 

A. Because the circulation and heat is 
greatest there. 

Q. What is a steam drum for ? 



— 22 — 

A. To have more volume and dryer 
steam. 

Q. Which is the hottest, steam or y/ater ? 

A. They are the same, only water will re- 
tain the heat longer, as water is a body and 
steam a vapor. 

Q. How should the circulation and feed 
be ? 

A. The circulation and feed should be 
continual. 

Q. Wliy? 

A. Because boilers have exploded just as 
the steam valve was opened to start the en- 
gine, after having stood still for some time. 
This is generally caused by the plates that are 
in contact with the fire becoming overheated, 
as the circulation being stopped after the 
steam is shut off. And just as soon as the 
valve is opened the pressure becomes les- 
sened, and the water on the overheated sheets 
flashes into steam of geeat elastic foece, 
and if the boiler is not strong enough, a ter- 
rific explosion is the result. 

Q. If you tried the gauge cocks and 
found no water in sight, what would you do ? 



— 23 — 

A. Simply put wet ashes over the fire and 
pull it out, raise flue caps and let the boiler 
cool down. 

Q. Why do you throw wet ashes over the 
fire before pulling it out ? 

A. If the fire was stirred up it would cre- 
ate more heat and be liable to burn the plates. 

The braces in the boiler should be exam- 
ined to see if they are loose, also the sheets, 
flues, heads and seams, to see if they are 
cracked or lealdng ; if they are not attended 
to, they may cause trouble and loss of life and 
limb. Engineers should not allow anything 
about the engine or boiler room to become 
greasy or dirty, for it shows poor manage- 
ment, and a careless, worthless engineer. If 
valves or cocks leak, they should be ground 
in with emery and oil until a seat or true 
bearing is found. 

Q. When should the boiler seams be 
corked ? 

A. When the boiler is empty and cold, 
for when the boiler is hot and filled with 
water, the jarring while corking would have 
a tendency to spring a leak somewhere else. 



— 24 — 

Q. Would you call pressure and weight 
the same ? 

A. No. 

Q. Why? 

A. Because pressure forces in every di- 
rection, while weight presses down. 

Q. Which is best, riveted or lap-welded 
flues? 

A. Lap-welded flues, as they are a true 
circle and not so easily collapsed as riveted 
flues. 

Q. Why? 

A. Because the riveted flues are not a 
true circle. 

Q. What is foaming ? 

A. Foaming is water and steam mixed 
together. 

Q. What causes foaming ? 

A. Dirty, greasy, oily and soapy water ; 
salt water forced into fresh water, also too 
much water and not enough steam room, will 
cause foaming. 

Q. What is priming? 

A. Priming is the lifting of water with 
steam, such as opening a valve suddenly, and 



— 25 — 

drawing water from the boiler to the cylinder 
of the engine. 

Q. What would you do in that case ? 

A. Close the throttle valve and leave it 
closed for a few minutes, then open slowly ; 
that will remedy it. Sometimes priming is 
caused by too much water and not enough 
steam room ; in this case carry a little less 
water. 

A. Are boilers sometimes injured by hy- 
draulic test ? 

A. Yes, if tested by an inexperienced 
person. Hydraulic test is the safest, because 
if the boiler is bursted no one is likely to get 
hurt. 

Q. If you had a high pressure of steam, 
and water was out of sight, would you raise 
the safety valve to let off the pressure ? 

A. No. 

Q. Why ? 

A. Because it would cause the water to 
rise, and when the valve closed the water 
would drop on the heated parts and be liable 
to cause an explosion. 

Q. If your boiler was too smaU to keep 



— 26 — 

up the amount of steam required, would you 
weight down the safety valve to carry a higher 
pressure ? 

A. No. 

Q. Why? 

A. Because that would show carelessness 
and a violation of the laws. There is no 
mystery about boiler explosions. They are 
simply caused by carelessness, and no man 
has the right to endanger the lives and prop- 
erty of others when he knows that he is in- 
competent to perform the duty required of 
him as engineer, whether licensed or other 
wise. 



HOW TO AVOID AND REMOVE SCALE 
FROM STEAM BOILERS. 



To counteract the impurities of water used 
in steam boilers, and to clean off the scale 
after it has formed, are two things upon 
which more thought and time has been be- 
stowed and money expended, with little or no 
result, than anything else connected with the 
use of steam ; in fact, to this very day, each 
engineer has his own crude way of getting at 
this difficulty, merely experimenting, hoping 
to find a remedy to overcome the evil. 

In our investigation of the many different 
articles sold for the removal and prevention 
of boiler scales, we have sent out very many 
letters of inquiry, and reports show that we 
have but one article now on the market 
which proves itself in every way reliable ; this 
article is manufactured in Philadelphia, Pa., 
and is known as Lord's Boiler Compound. 
All our reports show that this article is 



— 28 — 

unanimously endorsed by professional men 
throughout this continent, among whom are 
practical chemists, authors of mechanical 
books, engineers in charge of works, profes- 
sional inspectors and men having large capi- 
tal invested in steam boilers. 

The chemists for the U. S. Mint in Phila- 
delphia, Pa., testify under oath that Lord's 
Compound will not injure the iron, while 
other reports, also of the highest authority, 
show that where boilers were eaten up in a 
year or two by acids or corrosive matter in 
waters, no sign of injury has been found 
since Lord's Compound was first applied, in 
1876. 



PUMPS, 



Q. What kinds of pumps are there ? 

A. There are many kinds, but we con- 
sider only single action and double action for 
feeding boilers. 

Q. How many valves has a single action 
plunger pump ? 

A. Two valves, a receiving and a dis- 
charge. 

Q. How many valves has a double action ? 

A. Four, two receiving and two discharg- 
ing. The double action receives and dis- 
charges both ways. This kind of pump has 
a steam cylinder on one end. 

Q. How would you set up and level a 
pump ? 

A. Set the pump so the receiving is from 
the boiler and the discharge towards the 
boiler, put in the same size receiving and 
discharge pipe as tapped in the pump, so the 
pump can have a good supply and discharge. 



- — 30 — 

The pump is leveled with a spirit level or a 
square and plumb line. To level a double 
action pump, some level across the frame and 
along the piston ; the other way is to take 
the valve chamber cap off the water cylin- 
der and level the valve seats, so the valves 
wiU rise and drop plumb. To level a single 
action pump, take off the valve chamber caps 
and level both ways. 

Q. How is the water piston packed and 
w^ith what ? 

A. It is generally packed with square can- 
vas and rubber mixed packing ; it generally 
takes two pieces ; one piece is jointed on top, 
and the other on the bottom, to make what 
engineers call a broken joint. The packing 
runs from i to f inch square. These are the 
general sizes used for common sized pumps. 

Q. What other valve has a pump near the 
boiler ? 

A. A check valve. 

Q. What is a check valve for ? 

A. To check the water in the boiler from 
coming back, in case there is any work to be 
done on the pump. 



— 31 — 

Q. Could you pump water into the boiler 
if you had four or ^ve check valves on the 
discharge pipe ? 

A. Yes, I could force through all, but it 
would be more labor on the pump, because 
the plunger would have to force harder to 
raise the number of check valves. 

Q. Where is a pet cock put on pump bar- 
rel, and what for ? 

A. It is put at the side and near the bot- 
tom of the pump barrel, and is there to show 
how the pump is working, and to drain purap 
in winter to prevent freezing. 

Q. How do you know when your pump 
is in good working order ? 

A. By opening the pet cock and seeing 
the stream that comes out. 

Q. How does it show when in good work- 
ing order ? 

A. Nothing on the up-stroke and full 
force on the down-stroke. 

Q. Where would you locate the trouble 
if it came full force both strokes ? 

A. I would locate it at check and dis- 
charge valves, both being caught up ? 



— 32 -^ 

Q. Where would you locate the trouble 
if it came full force both strokes, moderate, 
tank or hydrant pressure ? 

A. At the receiving valve. 

Q. Can you run a pump witnoul a check 
valve ? 

A. If the discharge valve is in good order, 
yes ; but if there is neither check nor dis- 
charge, no. 

Q. Can you feed a boiler without a pump 
at all ? 

A. If the pressure of boiler is below the 
pressure of the feed water or city pressure, I 
can, by simply opening a water valve and let^ 
ting in the amount of water required. 

Q. What other way is a boiler fed? 

A. By an injector or an inspirator. 

Q. Must a pump have a valve ? 

A. Yes, if a pump had no valve it would 
not do any work. 

A pump is not a pump unless it has a 
valve. There are common well hand pumps 
with one valve, called a receiving or suction 
valve, but a force pump has two valves, a 
receiving and discharge ; the discharge is to 



— 33 -^ 

retain the water after it is delivered, so the 
plunger can get a fresh supply. After the 
plunger has ascended and begins to descend, 
the water sets on top of the receiving and un- 
der the discharge ; consequently, when the 
plunger descends it forces the receiving shut 
and the discharge open. 

Q. Should there not be another valve near 
the boiler ? 

A. Yes, a globe valve between the check 
valve and boiler. 

Q. What is that for ? 

A. To close and keep pressure in the 
boiler in case the check valve is caught up 
and needs repairing. 

Q. Can you raise, Kft or suck hot water 
with a pump ? 

A. Not very well. 

Q. ^Hay? 

A. Because the pump would get steam 
bound. Hot water should be level or higher 
than the pump in order to work well. 

Q. Where should a pet cock be put on 
the pump barrel for hot water ? 



— 34 — 

A. At the top of barrel, immediately nil' 
der the packing ring. 

Q. Why is it put there ? 

A. To let out steam when steam bound, 
and air when air bound. There should be a 
pet cock tapped in the cap of the valve 
chamber to let off steam or air when steam or 
air bound. 

Q. If you had no pet cock on the valve 
chamber cap, what would you do ? 

A. I would take a wrench and loosen one 
of the nuts a little until the air or steam was 
out, then tighten again. 

Q. Why is an air chamber put on a 
double action pump ? 

A. It is simply a copper vessel air tight. 
When the pump is working, the water is 
forced up into the chamber, compresses the 
air, and the air acts as a cushion on the valves 
and piston head in the water cylinder. 

Q. What is a cushion ? 

A. A cushion is anything that is com- 
pressed, and by its compression is formed into 
a higher and stronger pressure, consequently 
acting as a spring, deadening any knock that 



— 35 -. 

might have occurred otherwise, as water will 
cause a knock, it being nearly as solid as 
iron, so if a double action pump had no air 
chamber, there would be a continual thump- 
ing noise. 

Q. What is a vacuum ? 

A. A vacuum is a space void of matter. 

Q. Can a perfect vacuum be formed ? 

A. No, about 9 to 11 per cent, of the at- 
mosphere, which i5 14.7 pounds per square 
inch. 

Q . What will a vacuum do ? 

A. It will lift water 33 feet, providing all 
pipes and connections are air tight. 

Q. How is a vacuum created or made ? 

A. When the plunger of a pump is well 
packed and it lifts, it excludes the air out of 
the pump barrel and suction pipe, conse- 
quently the water, bei^ig at the other end of 
the pipe, it follows the plunger ; or, in other 
words, the atmospheric pressure, being 14.7 
pounds per square inch, forces the water up 
the pipe to fill the vacancy made by plunger 
forming the vacuum. 



— 36 — 

Q. What should be placed at the bottom 
of the suction pipe ? 

A. A strainer made out of gauze wire, 
a foot valve and a pet cock to drain it. 

Q. If your pump should not be working, 
your water running low, and you were asked 
to run a little while longer, would you run 
and let your water become dangerously low ? 

A. No, take no chances whatever, but 
shut down and go about repairing the trouble ; 

Q. Where would you look for the trouble ? 

A. Open the pet cock of the pump, and 
that will very nearly tell where to look for it ; 
if no water comes out, the water is shut oif, or 
there is none, etc. 

Q. What generally prevents a pump from 
working ? 

A. Not enough water, too small a suction 
pipe and obstructions of the valves to seat, by 
straws, sticks or anything that may be drawn 
through the suction pipe, or the pump valves 
becoming hot and sticking. 

Q. If an accident happened, such as a 
broken pipe connected with the boiler and 



— 37 — 

pump, or you could not get sufficient water to 
supply the boiler, what would you do ? 

A. Simply shut down the engine and all 
valves connected with the boiler, draw fire, 
raise flue caps, and close the damper, so as to 
keep water in the boiler until the difficulty is 
repaired. 

Q. If your suction pipe should spring a 
leak, what would you do ? 

A. Take a piece of sheet rubber, some 
copper wire, wrap around tight, and stop the 
leak temporarily. 

Q. If your hydrant, that supplies pump 
with water, should happen to get broken, 
what would you do ? 

A. First see how much water was in the 
boiler, by trying gauge-cocks, then shut off 
the water in the street, or wherever the lazy 
cock lay, and try to wrap it, if possible, or 
repair it. If an injector or inspirator "was 
attached, and was supphed from a tank or 
well, use them. 

Q. What is an injector or inspirator? 

A. They are a de\ace to answer for a 



-- 38 — 

pump in feeding a boiler ; they draw, force 
and heat the water at the same time. 

Q. For instance, if you had neither of 
these, what would you do ? 

A. Shut down the engine, close the 
damper, raise the flue caps and draw fire, 
whichever suited the circumstances. 

Q. If your pump was turned arouna, 
could you feed the boiler ? 

A. No. 

Q . What would be the consequence ? 

A. If the packing in the pump held out, 
the plunger would exclude the air and col- 
lapse the discharge pipe. 

Q. Would it not have a tendency to drain 
the water out of the boiler ? 

A. No, the check valve near the boiler 
would keep it back. 

Q. If you had no check valve, what would 
it do? 

A. The water would run out, that is, pro- 
viding the pump was turned around. 

Q. If the pump plunger is one-half the 
stroke of the engine, what should the diame- 
ter be ? 



— 39 ~ 

A. Oiie-thircl the diameter of engine cyl- 
inder. 

Q. How high should a valve lift to clear 
itself? 

A. About one-fourth of its diameter or 
one-third of its area. 

Q. What proportions should the valves 
be to any sized pump ? 

A. They should be one-fourth the area of 
the pumpc 



THE ENGINE 



Q. What is a steam engine ? 

A. A steam engine is a machine by which 
power is obtained from steam. 

Q. What is steam ? 

A. Steam is a gaseous vapor from water, 
generated from heat, composed of hydrogen 
and oxygen. 

Q. How do you know it is hydrogen and 
oxygen ? 

A. Science shows that 1 pound of hydro- 
gen with 8 pounds of oxygen is equal to 9 
pounds of water. 
~ Q. What is an engine composed of ? 

A. A bed plate, cylinder, connecting rod, 
crank, crank-shaft, main pillow block, tail 
pillow block, cross-head, wrist-pin in cross- 
head, crank-pin, two cylinder-heads, piston- 
rod, piston-head, follower head, bull-ring, 
packing-rings, follower plate and bolts, con- 
necting rod and brasses, pillow-block brasses, 
a valve, and guides where the cross-head 



— 41 — 

slides in, so the piston is kept central with 
the cylinder. The main pillow-block brasses 
are generally made into four pieces, called 
top, bottom and two quarter brasses each side 
of shaft ; they are made into four parts, so as 
to take up lost motion. 

Q. What keeps the rod from running off 
the crank pin? 

A. The shoulders on the crank-pin. 

Q." Why are the stub ends of straps made 
heavier where the gib and key passes through ? 
_ A. To make up for the amount of iron 
taken out for gib and key-way. 

Q. If water should accumulate in the cyl- 
inder, what would be the consequence ? 

A. It is liable to crack the cyhnder and 
disable the engine. 

Q. If you had charge of an engine in the 
country, and the cylinder head should happen 
to break, how would you remedy it ? 

A. If not broken too bad, try to patch it 
with pieces of iron or boards, and brace it 
from the wall with a piece of hewvy scantling, 
then try and run until anew cylinder head 
could be made. 



— 42 — 

Q. What size should a steam pipe and an 
exhaust pipe be to any size cylinder ? 

A. The steam pipe should be one-fourth 
and the exhaust one- third the diameter of the 
cylinder. 

Q. If your crank pin or other journals 
get hot, what would you do ? 

A. Try, while running, to get water on 
them, then oil them ; if that would not do, 
stop and slack up the key a little, then start, 
up again. 

All engine cylinders should be well drained 
and heated before starting, then the engine 
should be started slowly, as the water that 
accumulates in the cylinder may injure the 
piston, cylinder, or cylinder heads. Always 
leave the cylinder cocks open when not run- 
ning, and they should remain so until the 
cylinder is heated by the steam — after the 
engine has been running at full speed two or 
three minutes. 

Q. If the cylinder had shoulders inside, 
and was out of a true circle, what would you 
do? 

A. Bore it, or have it bored out. 



— 43 — 

Q. If your slide-valve was not steam- 
tight, what would you do ? 

A. Have the valve planed, then chip, file 
and scrape the seat to a full bearing. 

Q. If the crank and wrist-pins are worn 
out of true, what would you do ? 

A. Caliper and file them until they were 
round and true. 

Q. What causes the wrist-pin in the cross- 
head and crank-pin to wear the way they do ? 

A. It is simply the motion they have ; the 
crank goes all the way around and the wrist 
only vibrates. 

Q. If the cross-head or crank-pin brasses 
were brass-bound, what should be done ? 

A. They should be chipped and filed. 

Q. How do you know when you have 
taken enough off? 

A. By inside and outside calipers. 

Q. How does steam enter the cylinder ? 

A. In common slide-valve engines, it 
enters through one of the end ports and ex- 
hausts back through the same port, when the 
cavity of the valve has covered it and the 
exhaust port at the same time. 



— 44 — 

Q. What is a cavity ? 

A. It is a hollow space in the valve itself, 
TV here the exhaust passes through to the at- 
mosphere. 

On Corliss engines and other makes, there 
are separate valves, called exhaust valves ; a 
Corliss has two steam and two exhaust valves. 

Q. Where are they ? 

A. The two steam valves are on top, at 
each end of the cylinder, and the exhausts 
are at the two bottom ends. 

Q. What are the advantages of common 
slide-valve engines over other makes ? 

A. They are cheaper when first bought, 
more positive in their action, and simpler in 
design ; still, they are very wasteful. 

Q. If the throttle valve broke, and you 
could not stop the engine with the throttle, 
how would you stop it ? 

A. Lift the eccentric rod off the rocker 
arm-pin, and move the valve by hand v^ith a 
starting bar until the valve covers both ports 
equally, then the engine will come to a stop, 

Q. What is meant by a cushion in an 
engine cyhnder ? 



— 45 — 

A. Cushion is the resistance on. the oppo- 
site side of piston-head, formed by the steam 
being shut up in the cylinder, as the piston is 
nearing either dead center. 

Q. What is meant by clearance ? 

A. Clearance is the space between the 
piston head, cylinder head and valve face at 
each end of the stroke. 

Q. How would you know the amount of 
clearance there was m that space ? 

A. By finding the number of cubic inches 
in a bucket of water, then fill up the space 
level with the steam port, and see how much 
water is left in the bucket ; the difierence is 
the contents in cubic inches. 

Q. Why are gibs, keys and set screws 
used on both ends of connecting rod ? 

A. They are there to take up lost motion. 

Q. How would you do that? 

A. By loosening up the set screw, and 
driving down the key ; then tighten the set 
screw to keep the key from raising. 

Q. Is there more square inches in one 
end of the cylinder than the other ? 

A. In one sense of the word there are. 



— 46 — 

and in the other there are not, as the piston 
rod takes up some of the space in one end of 
the cylinder, therefore there is not the same 
area in one end as in the other. 

Q. What is a governor on an engine for ? 

A. It is to regulate the steam that passes 
from the boiler to th^ steam chest, when the 
throttle is wide open. 

Q. How does it work ? 

A. It is regulated to allow the engine to 
run at a certain speed. The governor has a 
belt from the main shaft to a pulley on the 
governor. After the engine is running up to 
the speed it is intended to, it allows only 
enough steam to enter through the governor 
valve to keep the same speed ; if the engine 
needs more power it begins to slack up, the 
governor balls drop, the valve opens and 
allows more steam to enter ; consequently, 
the engine must retain her speed ; and if the 
load is taken off it will start to run away, the 
governor balls will rise, force the valve shut, 
and cut off the steam ; consequently, the en- 
gine must come back to its regular speed. 

Q. How does a governor valve look ? 



— 47 — 

A. It IS a round valvo with grooves ; 
there are different kinds, some have three or 
four openings, and some only two ; the more 
openings the more sensitive the governor. 

Q. What is a lubricator for ? 

A. It is to saturate the steam that passes 
through the governor valve and the engine 
valve with oil, so they will not cut. The 
piston pa-cking rings and the cylinder are also 
oiled by the same oil. 



LINING AN ENGINE 



Q. How would you line up an engine ? 

A. By stripping the engine, take off both 
cylinder beads, if convenient ; .then take out 
the follower-head, piston-rings, bull-ring ; dis- 
connect the piston from cross-head ; also dis- 
connect the connecting-rod from the cross- 
head and crank-pin ; then take a slotted stick 
and place it on one of the studs on the end 
of cylinder furthest from the crank; then 
draw a fine sea-grass line over the point of 
stick and through the center of cylinder, and 
attach it to a stick at the other end of the 
bed-plate, nailed to the floor or clamped to the 
bed-plate ; then take a thin stick, the length 
of it being a half inch less than half the diam- 
eter of cylinder, and stick a pin in each end 
of the stick, so they can be forced in or drawn 
out to suit the adjustment ; then center the 
line at each end of the cylinder at the coun- 
ter-bore from four sides. Never center the 



— 49 — 

line in the stuffing box where the piston 
passes through, but use the inside counter- 
bore under all circumstances, whether you 
can remove the back cylinder head or not. 
Some engine cylinder heads and frames are 
one ; consequently, the head can not and must 
not be moved. 

Q. If one counter-bore would be out, or 
larger than the other, what would you do ? 
Would it not throw the bore of the cy Under 
or the line out ? 

A. No ; center it accordingly ; it would 
not make any difference, only two centering 
sticks with pins are needed to bring the line 
central with the bore. 

Q. Why do you use the counter-bore ? 

A. Because the counter-bore is the only 
true bore the cyhnder has that is not worn ; 
consequently, all engineers and machinists 
must go by it. 

Q. What is a counter-bore ? 

A. A counter-bore is each end of the cyl- 
inder bored fi^om ^ig to J of an inch larger, 
from 1 to 4 inches long, according to the 
size and length of the cylinder. 



. — 50 — 

Q. What is a counter-bore for ? 

A. To keep the piston from wearing a 
shoulder in the cylinder at each end. 

Q. Why is it that the piston does not 
wear a shoulder in the cylinder ? 

A. Because the piston rings just pass 
over the edge of the regular bore, and by so 
doing no shoulder can be formed in the cylin- 
der. 

Q. How is a cylinder bored? 

A. They are generally bored on a regular 
cylinder boring lathe, which has a table that 
can be raised or lowered to suit. The regu- 
lar bore is first bored, then the counter-bore, 
then the two faces for the heads. 

Q. How do you square a shaft when you 
have got the line centrally through the cylin- 
der? 

A. Move the crank-pin down to the line 
and see where the line touches the crank-pin 
between the two shoulders, then move the 
pin over to the other dead center, and see 
how it comes ; if equal, the shaft is square. 

Q. If you found it out of square -J inch, 
what would vou do ? 



— 51 — 

A. Move the tail-block. 

Q. Why not move the head-block ? 

A. Because it would alter the length of 
the connecting-rod, and be liable to knock out 
a cylinder-head. 

Q. How would you level a shaft ? 

A. A shaft is leveled by a spirit level, or 
a plumb-line dropped past close to the line 
that comes through the cylinder directly in 
front of the center of shaft ; let it drop in a 
bucket of water to keep the plumb-bob from 
swaying around ; then try the crank-pin at 
both half- strokes (the same principle as in 
squaring), top and bottom, and see how the 
crank-pin feels the line ; if equal, the shaft is 
level. 

Q. Is there no other way to level a shaft ? 

A. Yes, by the pulley wheel. 

Q. How is it done ? 

A. Drop a plumb line down from the 
ceiling, past the rim's edge of the wheel, di- 
rectly over the center of the shaft ; let the 
space between the plumb line and rim be one 
inch ; mark the wheel with chalk for a start- 
ing and stopping point, and caliper the dis- 



— 52 — 

tance with inside calipers ; then turn the 
wheel and shaft around, and continue caliper- 
ing until the wheel has made a full revolu- 
tion ; if it calipers the same all the way 
around, the shaft is level. This principle 
answers for tracing a wheel as well as leveling 
a shaft. The former way, by dropping a 
plumb line in front of the crank face and 
feeling the line with the crank-pin at both 
half-strokes, is the proper way to level a 
shaft. 

Q. If you found the shaft out of level^ 
what would you do ? 

A. I would have to thin or thicken the 
brasses, or babbitt the main pillow and tail- 
block bearings, whichever the case may be. 

Q. How would you know if the center of 
the shaft is in line with the line through the 
cylinder or not ? 

A. It can be found out by placing a two- 
foot steel square against the crank face, under 
the line through the cylinder, so that the heel 
of the square is at the center of the shaft, and 
see how the square touches the line ; if it 
touches exactly, the shaft is in line ; if too 



— 53 — 

hard, the shaft is too high ; if not at all, the 
shaft is too low. 

Q. How w^ould you raise your shaft ? 

A. There are various ways ; by liners, 
babbitt, heavier or hghter brasses. 

Q. If your crank face was oval, and you 
put a square against it, would that be right ? 

A. A spirit level could be placed on a 
square and bring it level, or drop a plumb- 
line, and put the end of the square against 
the crank-shaft center, and let it come against 
the plumb line. This is a very true way. 

Q. Now, after your shaft is in line, square 
and level, and you still find it out over line J 
inch, what would you do ? 

A. I would take it off the crank-pin 
brasses and fill in the other side with a brass 
ring, or babbitt the side edge of brasses ; in 
some cases the side of the connecting rod has 
to be chipped to allow it to pass free of the 
crank- face. 

Q. Why would you not take it off the 
wrist-pin brasses in the cross-head ? 

A. Because the rod would then be out of 
the center of cross-head, and would have a 



— 54 — 

tendency to bind the piston in the cyhnder 
and the cross-heads in the guides, consequent- 
ly cutting both. 

Q. Would it not make a difference on the 
other end of the rod ? 

A. No, the closer the crank-face the bet- 
ter. 

Q. NoAv what would you do ? 

A. Level and line the guides by putting 
them in their place, and line them with a pair 
of calipers, by calipering them at both ends 
to get them in line with the line through the 
cylinder, after having found the distance be- 
tween the side of the cross-head and the cen- 
ter of the cross-head where the piston enters 
the cross-head. Level by spirit level, first 
taking spirit level and trying it in the cylin- 
der, if a new one, or on top of the cylinder 
where it has been planed off when first bored, 
for they are the only things to go by. 

Q . Would you use the valve seat to level by? 

A. No, but alongside of it, where the 
steam-chest rests on. 

Q. If you had no spirit level, how would 
you do it ? 



— 55 — 

A. With a plumb-line, by placing a square 
lengthwise on the guides, and try them by 
bringing the square against the line. 

Q. If you had no two-foot square, and 
could not get any, how would you lay one off '^ 

A. Take a pair of dividers, draw a circle, 
then find four points on the circle, scribe lines 
from point to point, which gives a square. 
This should be done very accurately. 

Q. Can a plumb-line hang out of true ? ' 

A. It can not, providing it hangs clear of 
everything. If none of these were handy, a 
straight edge must be placed across the guides 
at one end, and see if the guides touch the 
straight edge equally at both edges, then cali- 
per the distance between the Hne and the 
straight edge, also at the other end of the 
guides ; if the same, the guides are level 
lengthwise with the cylinder and line ; then 
level the guides crosswise T\dth a plumb-line 
and square. 

Q. How would you measure your con- 
necting rod ? 

A. By finding the striking points. 

Q. How would you do that ? 



— 56 — 

A. By shoving the piston and cross-head 
up against the cylinder-head, and making a 
mark on the guides at one end of the cross- 
head with a scriber and center-punch ; then 
move the piston and cross-head back to the 
other cylinder-head and make another mark 
on the guide at the same end of the cross- 
head ; then measure from the center of crank- 
pin to center of shaft ; that gives the half- 
stroke ; double this, gives full stroke. If 
half -stroke is 12 inches, the full stroke is 24 
inches ; then if the distance between the two 
striking points is 25 inches, and the stroke 
24 inches, the clearance between the cylinder- 
head and piston-head will be i inch when the 
piston is at either end of the cylinder. Then 
move the cross-head -J- inch back from the 
striking point, and bring the crank-pin toward 
the same dead center, ; then take a tram and 
measure from the outside center of crank-pin 
to the outside center of wrist-pin in cross-head, 
which will give proper length of connecting- 
rod, also the right division of clearance. 

Q. What is meant by clearance in the cyl- 
inder ? 



— 57 — 

A. It is the unoccupied space between the 
piston-head, cylinder-head and valve-face, 
when the crank-pin is at either dead center. 

Q. Does the amount of clearance affect 
the engine's economy ? 

A. Yes, it does. 

Q. How much clearance should there be 
between the piston and cylinder-head ? 

A. It depends upon the size ; some have 
from J to f of an inch. 

Q. What is formed in that space or clear- 
ance when running ? 

A. A cushion. 

Q. What is a cushion ? 

A. A cushion means the steam that enters 
the cylinder through the lead the valve has, 
and the resistance it makes on the piston- 
head, cylinder-head and valve-face, as the en- 
gine is reaching the dead-center. 

Q. What is a cushion for ? 

A. It is to catch the piston and weight of 
the machinery as it reaches the dead center, 
and the lead is to give the engine power at 
the beginning of the stroke. 

Q. How does it act ? 



— 58 — 

A. The same as a spring on the end of a 
hammer. 

Q. If you wished to shorten, or lengthen 
the connecting-rod, how could it be done ? 

A. By placing tin or sheet iron liners be- 
tween the brasses and stub-ends of the con- 
necting-rod. 

Q. Now, if the key had to be raised, how 
could this be done ? 

A. By putting liners between the straps 
and brasses. 

Q. Would that not alter the length of the 
rod ? 

A. No. 

Q. With what instrument would you 
measure a connecting-rod ? 

A. It is called a "tram." 

Q . With what is an engine packed in the , 
stuffing-box ? 

A. Some engineers use hemp, others use 
black lead packing, and others use lead rings ; 
there are several kinds. Every engineer to 
his own taste. 



«-5?{5»i:^: 



VALVE MOTION 



Q. What is an eccentric ? 

A. An eccentric is a subterfuge for a 
crank ; it is something out of center. 

Q. How would you find the throw or 
stroke of an eccentric ? 

A. By measuring the heavy and the light 
side ; the difierence between the two is the 
stroke or throw. 

Q. What throw should a common shde 
valve engine eccentric have ? 

A. Generally double the width of the en- 
try or steam ports. 

Q. What is a cam ? 

A. A cam has no definite meaning ; it 
has 1, 2, 3 or 4 motions ; they are used on 
poppet valve engines, such as are in use on 
high pressure river steamboats. 

Q. How would you measure your valve 
and eccentric rods i 

A. By placing the crank-pin at its dead- 



— 60 — 

center, the center of the eccentric straight or 
plumb above the center of the shaft, the rock- 
er-arm perpendicular, and the valve covering 
both ports equally ; then take a tram and 
measure from the center of the eccentric to 
the center of the pin where the eccentric rod 
hooks on (generally the lower pin) for the ec- 
centric rod, and from the outside center of 
the pin where the valve-rod is attached to the 
furthermost end of the valve, allowing for two 
nuts at each end of the valve, called adjusting 
and jamb nuts. 

Q. How would you know the eccentric 
was plumb ? 

A, By dropping two plumb lines, one at 
each side of the shaft, and half the space be- 
tween the two lines will be where the center 
of the eccentric should stand, with the heavy 
side up. 

Q. What kind of a tool would you use to 
find the exact center ? 

A. A pair of hermaphrodite calipers, one 
leg of which has a sharp point and the other 
leg has a short foot, so as to feel the line. 

Q. What does an eccentric rod consist of ? 



— 61 — 

A. An eccentric rod consists of a strap, 
yoke, rod and two nuts ; when taking tlie 
measure, couple the yoke and strap together, 
then put a half-inch thick piece of wood be- 
tween the two straps and find the center of 
the circle from four sides, with a pair of her 
maphrodite calipers, then put the rod in the 
yoke and adjust it to the proper length by the 
two nuts ; if that will not do, the rod must 
be shortened or lengthened, by cutting out or 
adding a piece, whichever the case may be. 
Then take the measure with a tram from the 
center of the straps to the center of the rod 
where the rod hooks on the low^er rocker-arm 
pin. 

Q. How long is the thread on a valve-rod ? 

A. Long enough to allow two nuts at 
each end of the valve, and some space for ad- 
justment. 

Q. Now, if your rocker-arm stood at a 
quarter, and your eccentric out of plumb, 
how would you take the measure for the 
rods ? 

A. Simply bring them plumb and take 
the measure ; that is the only right way. 



— 62 — 

Q. After you have measured your rods, 
what would you do ? 

A. They should be put on and the valve set. 

Q. What do you move or do first, to set 
a valve ? 

A. Move the eccentric in the direction the 
engine is to run, until the valve begins to take 
steam or lead, then tighten the eccentric tem- 
porarily with set screws, then move the crank 
pin over to the other dead center, and see 
how much lead it has ; if equal, the valve is 
set. 

Q. What is meant by the lead of valve ? 

A. The opening the valve has when the 
piston is at the beginning of its stroke. 

Q. What lead should large engines have ? 

A. About fig of an inch. High speed en= 
gines must have a quick opening or good 
lead. 

Q. Now, if you find the valve laps out f 
of an inch on one end, and the proper lead on 
the other, what would you do ? 

A. Divide the difierence, by moving the 
valve one-half it is out, by adjusting the nuts 
on the valve gear. 



— 63 — 

Q. How much ? 

A. The valve has i^ of an inch lead at one 
end and laps f of an inch at the other end ; 
the valve is out h of an inch ; then the valve 
must be adjusted by the nuts one-half it is 
out, making ^2 of an inch. Then throw the 
crank on the other dead center, move the ec- 
centric whichever way will bring you back to 
iV of an inch lead, then tighten temporarily 
with set screws, throw crank over on the 
other dead center, and the valve will be set. 
After the valve is set, tighten the eccentric 
for good. 

Q. But if it is not set, what then ? 

A. Go through the same performance until 
it is set. Some valve-rods have a yoke that 
slips over the valve, while the adjusting and 
jam-nuts are between the stuffing box and the 
rocker-arm pin. When a valve-rod has no 
nuts, the adjusting must be done at the eccen- 
tric rod. To lengthen or shorten the stroke 
of valve-rod, raise or lower the eccentric-rod 
pin in the slot, at the bottom of the rocker- 
arm, whichever way suits the circumstances. 

Q Now, after you have set your valve, 



~ 64 — 

keyed everything up properly, and there was 
a thud or dead sound in the engine or cylin- 
der, what would you do, or where would you 
look for the trouble ? 

A. In the exhaust being choked. The 
steam-chest cover must be taken off, then un- 
couple the valve, turn the valve up sideways 
and move it until the steam edge has the 
proper lead with the steam-port, then place a 
square on the valve- seat of the cylinder, and 
against the valve- face, to see how the ex- 
haust lead on the opposite steam port corre- 
sponds ; if it is choked, then scribe it by al- 
lowing a little over double the steam lead. 

Q. How would you make the exhaust 
larger? 

A. By chipping it out of the exhaust cav- 
ity in the valve, and rubbing a hie over it to 
smooth it. 

Q. Do you think a little over double the 
steam-lead would be sufficient ? 

A. Yes ; if not, take out a little more. 

Q. Where should the exhaust be ? 

A. It should be the furthest from the 
steam-port that is receiving. 



— 65 — 

Q. Wliat would you do in case your ec- 
centric slipped ? 

A. Set the valve the same as before. 

Q. Is the principle of valve setthig the 
same ? 

A. Yes ; some engines have two steam 
and two exhaust valves, -but that makes no 
difference, the principle is the same. 

Q. How would you find the dead center 
of an engine ? 

A. By placing a spirit level on the strap 
that goes around the brasses that connect the 
crank-pin to the connecting-rod, and when it 
is level the crank is at dead center. If the 
engine is not level, then an adjustable level 
must be used. 

Q. What other way could you find the 
dead center of an engine ? 

A. By moving the engine toward the dead 
center until the cross-head stopped moving ; 
then put a center punch mark in the floor, 
and one on the fly-wheel, after having marked 
it with a tram ; then move the crank over the 
center until the cross-heads begin to move, 
then put another mark ; the middle between 



— 66 — 

the two marks is the exact dead center ; then 
bring the middle mark to the point of the 
tram ; this is done with a small tram with 
one straight point and a short foot. 

Q. If the engine had to be run in the op- 
posite direction to which it had been running, 
how could it be done ? 

A. It could be done by placing the crank- 
pin on the dead center, removing the steam- 
chest cover, and turning the eccentric over on 
the shaft in the opposite direction, until the 
valve has the proper lead at the opposite port, 
then try the engine from dead center to dead 
center, to equalize the lead at both ends of the 
valve ; then the engine will run in the oppo- 
site direction. 

Q. Does a crank-pin and piston travel the 
same distance ? 

A. No, a crank-pin travels liWo\ times 
further than the piston each revolution, or 
^- AWo times further each stroke. For exam- 
ple, take an engine with a 12-inch stroke, the 
piston travels 24 inches and the crank-pin 
37i^owo inches each revolution, or the piston 
travels 12 inches each stroke and the crank -pin 



— 67 — 

13.6992 per single stroke of piston. To do 
this, multiply the single stroke by 3.1416 and 
subtract the double stroke from the answer ; 
the remainder will be the distance the crank- 
pin travels further than the piston. This rule 
answers for all engines. Another fact not 
generally known by many men is that a crank 
of an engine, at two certain points, travels a 
long distance while the motion of the cross- 
head is hardly noticed. 

When the center of the crank-shaft and 
crank-pin are in line with the piston-rod, no 
steam pressure applied to either side of the 
piston can set the engine in motion ; this is 
called the dead center. 

Q. What is a revolution ? 

A. It means the crank has turned once 
around, or made a circle. 

Q. How many strokes has a revolution ? 

A. Two. 

Example : If an engine has 24 inches 
stroke, and makes 65 revolutions per minu*te, 
how many feet does it travel in a minute ? 
24 inches multiplied by 2 equals 48 inches, 
this multiplied by 65 revolutions equals 3120 



-- QS — 

inches, which divided by 12 equals 260 feet 
per minute. 

Q. If you were asked the horse power of 
any sized engine, could you tell it ? 

A. Yes. 

Q. Well, how would you go about it, and 
what is a horse power ? 

A. A horse power is 33,000 pounds raised 
1 foot high in 1 minute, or 150 pounds raised 
220 feet high in 1 minute. To find the horse 
power of any engine, first find the area of the 
piston-head face, then multiply the answer by 
the average pounds pressure per square inch, 
then multiply by the number of feet traveled 
in 1 minute, and divide by 33,000. 

EXAMPLE : 
Cylinder 12 x 24 in. 12 diam. of cylinder. 

66 revolutions, 12 

Average pressure 80 ft)s. 144 sq. of diameter. 

.7854 



113.0976 area of p. h. face. 
80 average pressure. 



9047.8080 

260 No. ft. trav. by p. 



33000)2352430.0800(71.2857 horse pow. 



THE INDICATOR 



The steam engine indicator is an instru- 
ment for showing the pressure of steam in the 
cylinder at all points of the stroke, or for 
producing actual diagrams. The indicator 
consists of a small cylinder accurately bored 
out, and fitted with a piston, capable of work- 
ing in the (indicator) cylinder with little or no 
friction, and yet be practically steam-tight. 
The piston has an area of just |^ of a square 
inch, and its motion in the cylinder is ff of 
an inch. 

The piston-rod is connected to a pair of 
light levers, so linked together that a pencil 
carried at the center of the link moves in 
nearly a straight line through a maximum 
distance of 3|- inches. A spiral spring placed 
in the cylinder above the piston, and of a 
strength proportioned to the steam pressure, 
resists the motion of the piston ; and the elas- 
ticity of this spring is such that each pound 
of pressure on the piston causes the pencil to 



■ — 70 — 

move a certain fractional part of an inch. 
The pencil in this case is made of a piece of 
pointed brass wire, which retains its sharp- 
ness for a considerable time, and yet makes a 
well-defined line upon the prepared paper 
generally used with the indicator. 

The paper is wound around the drum, 
which has a diameter of 2 inches, and is cap- 
able of a semi-rotary motion upon its axis to 
such an extent that the extreme length of dia- 
gram may be SJ inches. Motion is given to 
the drum in one direction, during the forward 
stroke of the engine, by means of a cord con- 
nected indirectly to the cross- head of the 
engine, and the drum is brought back again 
during the return stroke of the engine by the 
action of a coiled spring at its base. 

The conical stem of the instrument permits 
it to be turned around and fixed in any de- 
sired position, and the guide-pulleys attached 
to the instrument under the paper drum may 
also be moved around so as to bring the cord 
upon the drum-pulley from any convenient 
direction. 

The upper side of the piston is open to the 



— 71 — 

atmosphere ; the lower side may, by means 
of a stop-cock, be put into communication 
either with the atmosphere or with the engine 
cyhnder. 

When both sides of the piston are pressed 
upon by the atmosphere, the pencil, on being 
brought into contact with the moving paper, 
describes the atmospheric line. When the 
lower side of the piston is in communication 
with the engine cylinder^ the position of the 
pencil is determined by the pressure of the 
steam existing in the cylinder ; and on the 
pencil being pressed against the paper during 
a complete double stroke of the engine, the 
entire indicator diagram is described. 

In order that the diagram shall be correct, 
the motion of the drum and paper shall coin- 
cide exactly with that of the engine piston ; 
second, that the position of the pencil shall 
precisely indicate the pressure of steam in the 
cylinder ; third, that the pendulum must be 
from H to 3 times as long as the stroke 
of the engine piston ; fourth, that the pendu- 
lum must be plumb when the piston is at half- 
stroke ; fifth, that the cord around the drum 



^72 — 

must be attached to the penduhim at right 
angles, or square with the indicator ; sixth, 
the pendulum must be attached with an inch 
wooden pin to the ceiling or floor at one end, 
the other end to the cross-head by means of a 
screw-bolt in the wrist-pin and a slot in the 
pendulum ; seventh, that the two holes tapped 
in the cylinder are directly opposite the steam 
ports, and centrally between the piston-head 
and cylinder head, when the engine is at the 
dead center, or, in other words, in the center 
of clearance ; eighth, that the piping should 
be as short as possible, and -J- inch pipe if not 
over 1 foot long. If longer the pipe should 
be larger close to the cylinder, and covered 
so as not to allow too much condensation, as 
it aflects the diagram. The best way to take 
a aiagram is to tap a hole in each cylinder-head 
and take each end separately. The cord must 
be attached to the pendulum, so the paper 
drum will move in proportion to the piston. 
An indicator shows the highest and the 
lowest pressure reached, also the cut-off and 
lead. If there is a great difference, say more 
than 5 pounds, between the boiler pressure 



— 73 — 

and the initial pressure upon the piston, the 
connecting pipes may be taken as being too 
small, too abrupt, or the steam ports too con- 
tracted. The full pressure of steam should 
come upon the piston at the very beginning 
of its stroke. Should the admission corner be 
rounded, the valve is wanting in " lead," or, 
in other words, the port for the admission of 
steam is uncovered too late in the stroke. 

The steam line should be parallel or 
straight with the atmospheric line up to the 
point of cut-off, or nearly so. Should it (the 
steam line) fall as the piston advances, the 
opening for the admission of steam is insuffi- 
cient, and the steam is " wire-drawn." 

The point of cut-off should be sharp and 
well defined ; should it be otherwise, the 
valve does not close quick enough. The 
bevel line leading from the cut-off line to the 
end of the stroke is called the expansion line. 

Q. What is the standard indicator ? 

A. The Tabor's improved. 

Q. Are there any other makes ? 

A. Yes ; Richard's, McNought's, Thomp- 
son's and others. 



RULES 



KuLE for telling the power of a diagram : 
Set down the length of the spaces formed by 
the vertical lines from the base in measure- 
ments of a scale accompanying the indicator, 
and on which a tenth of an inch usually rep- 
resents a pound of pressure ; add up the total 
length of all the spaces, which will give the 
main length, or the mean pressure upon the 
piston in pounds per square inch ; to do this, 
lay a card taken by the indicator ofl' in ten 
parts, by drawing lines from top to bottom. 
Find out what the scale is ; suppose it is 60, 
the number of ordinates 10, and that the sum 
of their length is 6 inches ; so 6 and 10 
ordinates = /^ ^r .6 x 60 == 36.0. Answer, 
36 pounds pressure upon the piston. 

EuLE for finding and deducting friction : 
Multiply N. H. P. by .13 and subtract the 
answer from N. H. R , which gives I. H. P. 

Q. What is N. H. P. ? 

A. It is nominal horse power. 



— 75 — 

Q. What is I. H. P. ? 

A. It is indicated horse power. 

Q. What is meant by cutting off steam at 
6 inches? 

A. It means that the valve closes and cats 
off the live steam from the boiler at 6 inches 
of the piston's travel ; then the engine gets 
its power, from the time the valve closes or 
cuts off until the exhaust opens, by the expan- 
sion of the steam closed up in the cylinder. 

Standard multipliers, with examples : 

1, For the Area of a Circle, Multiply sq. of diam. by .7854 

3. For Circumference of a Circle, Multiply diameter by 3.1416 

3. For Diameter of a Circle , Multiply circum. by .31831 

4. For the Surface of a Ball, Multiply sq. of diam. by 3.1416 

5. For the Cubiclnches in a Ball, Multiply Cube of di. by .5336 

1 . Rule for finding the area of any circle. 
Always multiply the diameter by itself, then 
by .Y854, then cut off 4 decimals to the right. 

2. Rule for finding the circumference of 
anything round. Multiply the diameter by 
3.1416, and cut off 4 decimals. 

3. Rule to find the diameter of a circle. 

Multiply circumference by .31831. 

Example: The circumference 9.4248 x .31831 = 
3.000008088 -= 3 inches diameter. 



— 76 — 

4. Rule to find the surface of a sphere, 

globe or ball. 

Example: 9 inches diameter x 9 = 81 x 3.1416 = 
254.4696. 

5 . Rule to find the cubic inches in a ball. 

Multiply cube of the diameter by .5236 ; the 

answer equals its solid contents. 

Example : Ball 3 inches in diameter ; 3x3 = 9; 
9 X 3 = 27 X .5236 = 14i\,Wo- solid contents. 

Rule to find the pressure on the crown 
sheet of a hanging fire-box boiler. Multiply 
the width by the length in inches, then multi- 
ply by steam gauge pressure and divide by 2. 

EXAMPLE : 
Crown sheet 46 x 33 in. 46 

Pressure 85 lbs. 33 

Iron ^ in. 1518 

85 



If iron is X i^. div. by 4. 2)129030 
If iron is )i in. div. by 2.66 2000)64515 lbs. press'e. 

32.^^ tons " 
Rule to find how much water a boiler will 
contain. For 2-flue boiler, f full of water, 
find f of the area of the boiler in inches in- 
side ; multiply by length in inches ; then find 



— 77 — 

area of flues, thickness of iron added ; then 
multiply by 2, if 2 flues ; multiply by length 
in inches, subtract area of flues from f con- 
tents, and divide by 231 (number of cubic 
inches in a standard gallon) ; the answer will 
be the number of U. S. standard gallons. 

EXAMPLE : 
Boiler 48 inches. 48 
Two flues, 16 in. each. 48 

Length 20 feet. 2304 

16 .7854 



16 

256 

.7854 


3)1809.5616 Area of Boiler. 

603.] 872 One-third of Area. 

2 


201.0624 
2 


1206.3744 Two-thirds of area 
240 Length in inches. 


402.1248 
240 


289529.8560 
96509 9520 Sub. Area of Flues. 


96509.9520 231)193019.9040 



835.5840 No. of Gallons. 
EuLE to find the amount of water required, 
when the average pounds of coal used per 
hour is known. Divide the coal by 7.5 ; the 
answer will be cubic feet ; then multiply by 
7.5, and that gives the number of U. S. 
standard gallons. 



— 78 — 

EXAMPLE : 
117 tt)s. of coal used per hour, 7.5)117.0 

15 
7.5 

112.5 = 112X gals. 

Q. How many cubic feet in 1 ft), of air ? 

A. 13/oVo cubic feet. 

Q. How much air does it take to consume 
1 pound of coal ? 

A. It takes 18 pounds, or 24:8j^o% cubic 
feet. 

Q. How would you tell the amount of 
water any tank contained ? 

A. If the tank was large at the bottom 
and narrow at the top, lay the tank off in 10 
parts from top to bottom, then take the diam- 
eter 1^ from the large end of the tank, square 
it, then multiply by .7854; that gives the 
area ; then multiply quotient by full depth of 
tank and divide by 1728, which gives the 
number of cubic feet ; multiply answer by 
7. 5, and the number of U. S. gallons will be 
given. The example must be done in inches ; 
1728 is the number of inches in a cubic foot, 
and 7. 5 is the number of gallons in a cubic foot. 



-- 79 — 

EXAMPLE : 
Tank 2 feet di am. 24 inches diameter. 

Tank 3 feet deep. 24 " " 

576 
.7854 

452.3904 area in inches. 
36 inches deep. 



1728)16286.0544 



9.4248 cubic feet. 

7.5 No. gals, in cub. ft. 



70.68600 U. S. gals, in tank. 

Rule how to mark engineer's tools. Warm 
the tool and allow a thin coat of beeswax to 
cover the place to be marked ; after the bees- 
wax is cold, take a dull scriber and do the 
marking ; then apply some nitric acid, after 
a few moments wash off the acid with water, 
then heat the tool to melt the beeswax, and 
you mil find well defined marks. 

Rule for chimneys. Chimneys should be 
round inside, instead of square, to insure a 
good draft. The opening should be one-fifth 
larger than the area of the flues or tubes com- 
bined ; if less, the draft will not be free. The 
opening from the bottom should increase in size 
to the top, and be as smooth as possible inside. 



— 80 — 

Rule for making good babbitt metal, for 
high and low speed, in parts. 



HIGH SPEED. 1 


COMMON. 


MEDIUM. 


Martin's Nickel . . 


10 
16 

4 

70 

100 


CoDDPr 


13 

4 
84 


CoDDer 


(-0 


Copper 


Antimony 

Tin 


Antimony 

Tin 


'^^ 


Antimonv. 


1*1 


Tha y.;:;::::: 












100 




100 



Rule for babbitting a box. Nearly every 
engineer has his own way ; but the best and 
quickest way is to chip out all the old bab- 
bitt in the cap and box, then put the journal 
or shaft that is to run in the box in its place ; 
put enough liners in between the shaft or 
journal and edge of box until level, square 
and in line ; put thick putty around the shaft 
and against the box, so the babbitt can not 
run out ; then heat the babbitt until it runs 
free, and pour accordingly ; the cap is then 
bolted in its place upon ^^ inch thick liner, 
and putty placed as before ; then pour the 
metal through the oil holes, which will have 
to be drilled out afterwards. 

Rule to determine the capacity of any 
size pump, single or double action. Multiply 
the area of the water piston-head face or 



— 81 — 

plunger in inches, by its stroke in inches, 
which gives the number of cubic inches per 
single stroke ; the answer divided by 231 
(the cubic inches in a gallon) will give 
the number of standard gallons per single 
stroke. But remember, all pumps throw 
less water than their capacity, which de- 
pends upon the condition and quahty of the 
pump. This loss arises from the rise and fall 
of the valves ; from a bad fit or leakage, and 
in some cases from there being too much 
space between the valves, piston or plunger. 
The higher the valves have to rise to give the 
proper opening, the less work the pump will 
perform. 

Q. Will a boiler 60 inches in diameter, 
f inch iron, stand as much pressure as a 
boiler 48 inch diameter, f inch iron ? 

A. No. 

Q. Why? 

A. Because the pressure in the large 
boiler has more surface, and mil not allow it. 
It is the same as a long bar and a short bar 
of the same thickness ; it takes less strain to 
break the long one than the short one. 



— 82 -^ 

Rule for finding safe working pressure of 
steam boilers. Always use .56 for single 
riveted and .70 for double riveted side seams, 
A radius means one-half the diameter ; and 
one-fifth of the tensile strength is the safe 
load. U. S. standard is one-sixth. 

Multiply the thickness of iron by single or 

double rivets, then multiply by the safe load, 

divide by internal radius, and the answer will 

be the safe working pressure. 

EXAMPLE : 
Diam. 42 in. .1875 thickness of iron. 

Iron -^^g in. .70 double riveted. 

Double riveted and .131250 

50,000 lbs. tensile str'th. 10000 2)42 

20.812 5)13125000.00 21 outside radius. 
Safe working pressure. 63.06 .1875 

5 20.8125 inside rad. 
Bursting pressure. 315.30 

Rule to find aggregate strain caused, hy 
the pressure of steam on the shells of boilers. 
Multiply the circumference in inches by the 
length in inches ; multiply this answer by the 
pressure in pounds. The result will be the 
pressure on the shell of boiler, and divide by 
2000, which gives the tons. 



— 83 — 

EXAMPLE : 

Diam. of boiler 48 inches, circumference 150.7968, 
leii.o^ih 20 feet, or 240 inches, pressure of steam 120 lbs. 
150.7968 X 240 X 120 = 4342947.8400 lbs., divided by 
2000 = 2171^ tons strain. 

Rule to find the number of feet of 1 inch 
pipe required to heat any size room with 
steam. For direct radiation 1 lineal foot 
(straight foot) to 25 cubic feet of space. For 
indirect radiation, 1 lineal foot to 15 cubic 
feet of space. Note, all pipe is measured in- 
side for size. 

EXAMPLE : 

Room 18 X 18 X 18 to be heated with 1 inch pipe. 

Direct radiation. All calculating must be done In 

inches, and divided by 1728 to give the cubic feet. 

216 

216 



46656 
216 



1728)10077696 cubic inches. 



25)5832 cubic feet. 

Lineal 2332^5 feet of 1 inch pipe. 

One cubic foot of boiler is required for 

every 1500 cubic feet of space to be warmed. 

One horse power of boiler is enough for 

40,000 cubic feet of space. 



— 84 — 

EuLE to find the horse power of a boiler. 
Always find the number of square inches and 
divide by 144, which gives the square feet of 
heating surface, and divide by 15 square feet, 
which is an average allowance for one horse 
power of a boiler ; divide the H. P. by 2, 
you will have the proper grate surface, and 
allow i square inch m safety valve to each 
square foot of grate surface. Generally, from 
•| to f of a square foot of grate surface is al- 
lowed to each horse power of a boiler. 

Q. How do you find the horse power of a 
boiler? 

A. Find the number of square feet of 
heating surface and divide by 15 ; 15 square 
feet of heating surface is the general allow- 
ance for a H. P. of a boiler. (See following 
example.) 



— 85 — 

EXAMPLE : 
Boiler 48 in. x 25 ft. First find circum. of boiler. 

Two 16 in. flues. 16 diam. of 1 flue. 

48 diam. of shell. 3.14 16 

3.1416 50.2656 circ. of 1 flue. 

3)150.7968 



50.2656 one-third circum. 15079.6800 in inches. 
2 2 



100.5312 two-thirds '• 30159.3600 heat. sur. 2 fl. 
300 length or boiler in inches. 



30159.3600 Js^o. sq. in. heat. surf. 16 in diam. of 1 flue, 

in the shell. J^ 

48 256 

48 .7854 



2304 201.0624 area 1 flue. 

.7854 2 



3)1809.5616 area of 1 head. 402.1248 area 2 flues. 

603.1872 one-third area of 1 hd^ 2 

2 804.2496 both ends. 



1206.3744 two-thirds area of 1 hd. 
2 



2412.7488 two-thirds area both hds. 
No. sq. in. heat. surf, in shell, 30159.3600 
" '' " flues, 30159.3600 

Two-thirds area both heads, 2412 .7488 

Total, 62731.4688 

Subtract area of flues, 804.2496 
This boiler is 28 h. p. An 144)6 1927.2192 

engineuses about ^ of boil- 15)430. sq. ft. h. s. 

er'sh. p., making this boil- 2)28. h. p. 

er sufficiently large enough 2(lA. grate surf, 

to supply engine of 84 h. p. 7. area s'fty v. 



_. 86 — 

Rule to find the horse power generated in 
any kind of boiler when running. First, no- 
tice how long it will take to evaporate 1 inch 
of water in the glass gauge, divide this into 
60, which gives the number of inches evap- 
orated in one hour ; second, multiply the 
average diameter where evaporation took 
place by the length of the boiler in inches ; 
this multiplied by the number of inches evap- 
orated, and the answer divided by 1728 gives 
the cubic feet of water evaporated in one 
hour. 

As a rule, 1 cubic foot of water evaporated 

is generally allowed for 1 horse power ; also 

the capacity of a pump or injector for any 

boiler should deliver 1 cubic foot of water 

each horse power per hour, and an engine 

uses one-third of a cubic foot of water per 

horse power. 

EXAMPLE : 

Length of boiler 216 inches. 216 

Average diam. 40 inches. 40 

One inch evaporated in 15)60 8640 

15 minutes. 4 4 

1728 )34560 

20 horse power 



— 87 " 

Weight op Square Superficial Foot of Boiler 
Plate when Thickness is Known. 



Thickness. 


Weight. 


Thickness. 


Weight. 


Inches. Dec. 


lbs. 


Inches. Dec. 


• lbs. 


^1. = .03125 


1.25 


A = .3125 


12.58 


,\ = .0625 


2.519 


1 =.375 


15.10 


3^2 = .0937 


3.7SS 


A = .4375 


17.65 


i = .125 


5.054 


i = .5 


20.20 


;% = .1562 


6.305 


A = .5625 


22.76 


A = .1875 


7.578 


f = .625. 


25.16 


3^, = .2187 


8.19 


f =.75 


30.20 


i = .25 


10.09 


1 = .875 


35.30 


3^2 = 2812 


11.38 


1=1 


40.40 



Q. Explain how the above fractional 
parts of whole numbers are made to read as 
decimals — take ^ of an inch for an example ? 

A. To do this, take 100 as a whole num- 
ber ; 16 into 100 is . 625 X 3 = .1875. This 
principle answers for all the rest. 

Rule for safety valves. To find the dis- 
tance ball should be placed on lever, when the 
weight is known, or the distance is known 
and weight is not known. Multiply the 
pressure required by area of valve, multiply 
the answer by the fulcrum ; subtract the 
weight of the lever, valve and stem, and di- 



vide by the weight of ball for distance, or di- 
vide by distance for the weight of ball with 
the same example as follows : 

EXAMPLE : 

Weight of ball, 60 lbs. 100 lbs. pressure. 

Pressure, 100 " 3 area of valve. 

Wt. of L. V. & stem, 30 " 300 

Fulcrum, 4 inch. 4 fulcrum. 



Areaofvalvd^ 3 " 1200 

30 wt. of L. Y. & St. 



60)1170 

19^ inch ball should 
be hung on lever. 

The mean effective weight of valve, lever 
and stem is found by connecting the lever at 
fulcrum, tie the valve-stem to lever with a 
string, attach a spring scale to lever immedi- 
ately over valve, and raise until the valve is 
clear of its seat, which will give the me^n 
effective weight of lever, valve and stem. 

Rule for figuring the safety valve and to 
know the pressure, when the area of valve, 
the w^eight of lever, valve and stem, the dis- 
tance fulcrum is from valve, and weight of 
ball is known. 



— 89 — 

Divide fulcrum into length of lever, multi- 
ply answer by weight of ball, add weight of 
lever, valve and stem, and divide by area of 
valve. Answer will be steam pressure. 

EXAMPLE : 

Weight of ball, 50 lbs 2.25 4)20 

Wt, of L. V. and stem, 30 lbs 2.25 ^ 

Fulcrum, 4 in. 5.0625 50 

Diam. of valve, 2^ in. .7854 * 250 

20 '* 3.97608750 area. 30 



Add as many ciphers to the divi- 3-9)280.0 

dend as there are decimals in the di- lbs. press. 71. |^ 
visor, and divide as whole numbers. 

To measure or mark off the lever, you 
measure the fulcrum and make notches the 
same distance as fulcrum ; if fulcrum is 4 
inches, each notch must be 4 inches apart. 

Q. What is meant by a fulcrum ? 

A. The distance valve stem is from where 
the lever is connected. 



RULES, 



Rule to Gear a Lathe for Screw Cut- 
ting. — Every screw cutting lathe contains 
a long screw called the lead screw, which 
feeds the carriage of the lathe while cutting 
screws ; upon the end of this screw is placed 
a gear to which is transmitted motion from 
another gear placed on the end of the spindle ; 
these gears each contain a different number 
of teeth, for the purpose of cutting different 
threads, and the threads are cut a certain 
number to the inch, varying from 1 to 50. 
Therefore, to find the proper gears to cut a 
certain number of threads to the inch, you 
will first multiply the number of threads you 
desire to cut to the inch by any small num- 
ber, 4 for instance, and this will give you the 
proper gear to put on the lead screw. Then 
with the same number, 4, multiply the num 
ber of threads to the inch in the lead screw, 
and this will give you the proper gear to put 
on the spindle. For example, if you want to 
cut 12 to-the inch, multiply 12 by 4, and it 
will give you 48. Put this gear on the lead 
screw, then with the same number, 4, multi- 



-- 91 — 

ply the number of threads to . the inch in the 
lead screw. If it is 5, for instance, it will 
give you 20 ; put this on the spindle and 
your lathe is geared. If the lead screw is 4, 
5, 6, 7 or 8, the same rule holds good. Al- 
ways multiply the number of threads to be 
cut first. Some — indeed, most small lathes 
— are now made with a stud geared into the 
spindle, which stud only runs half as fast as 
the spindle, and in finding the gears for these 
lathes you w^ill first multiply the number of 
threads to be cut, as before, and then multi- 
ply the number of threads on the lead screw 
as dpuble the number it is.* For instance, if 
you want to cut 10 to the inch, multiply by 
4, and you get 40 ; put this on the lead 
screw ; then, if your lead screw is 5 to the 
inch, you caU. it 10, and multiply by 4, and 
it will give you 40. Again put this on your 
stud and your lathe is geared, ready to com- 
mence cutting. 

EULE FOR CUTTING A SCREW IN AN EnGINE 

Lathe.— In cutting Y-thread screws, it is only 
necessary for you to practice operating the 
shipper and slide screw-handle of your lathe 
before cutting. After having done this until 
you get the motions, you may set the point 
of the tool as high as the center, and if you 
keep the tool sharp you wiU find no difficulty 



— 92 — 

in cutting screws. You must, however, cut 
very light chips, mere scrapings in finishing, 
and must take it out of the lathe often, 
and look at it from both sides very carefully, 
to see that the threads do not lean like fish 
scales. After cutting, pohsh with a stick and 
some emery and oil. 

EuLE FOR Cutting Square Thread 
Screws. — ^In cutting^ square thread-screws, it 
is always necessary to get the depth required 
with a tool somewhat thinner than one-half 
the pitch of the thread. After doing this, 
make another tool exactly one-half the pitch 
of the thread, and use it to finish with, cut- 
ting a slight chip on each side of the groove. 
After doing this, polish with a pine stick and 
some emery. Square threads for strength 
should be cut one-half the depth of their 
pitch, while square threads for wear may — 
and should be — cut three-fourths the depth of 
their pitch. 

EuLE FOR Mongrel Threads. — Mongrel, 
or half V half square threads, are usually 
made for great wear, and should be cut the 
depth of their pitch, and for extraordinary 
wear they may even be cut 1^ the depth of 
the pitch. The point and the bottom of the 
grooves should be in width J the depth of 
their pitch. What is meant here by the 



— 93 — 

point of the thread is the outside surface ; 
and the bottom of the groove is the groove 
between the threads. In cutting these threads 
it is necessary to use a tool about the shape 
of the thread, and in thickness about one-fifth 
less than the thread is when finished. As it 
is impossible to cut the whole surface at once, 
you will cut it in depth about ^e at a time, 
then a chip off the sides of the thread, and 
continue in this way alternately till you have 
arrived at the depth required. Make a gauge 
of the size required between the threads and 
finish by scraping with water. It is usually 
best to leave such screws as these a little 
large until after they are cut, and then turn 
off a light chip, to size them ; this leaves them 
true and nice. 

EuLE TO Temper Tools used daily, such 
AS Chisels, Taps, Dies, Reamees, Twist 
Deills, Common Flat Deills, and Lathe 
Tools. — To temper flat, cape or side chisels, 
and common flat drills, put the tool to 
be tempered in the fire and heat slowly to a 
cherry red color, about 4 inches from the 
point. Then take it out and put it in the 
water, point first, about three or four inches, 
then draw it back quick about an inch from 
the point, and leave it so until the water will 
barely dry on the chisel, then take it out, 



— 94 — 

polish it with a piece of sand stone, and let 
the heat that is left in the body of the tool 
force its way toward the point ; it will be 
noticed immediately in the change of color. 
The color of temper for chisels to cut cast iron 
should be a dark straw, turning to a blue. 
The temper of chisels to cut wrought iron or 
steel should be plunged into water after the 
dark straw color has disappeared and the blue 
begins to show itself, and left in the water to 
cool off. In some cases, where the tool is too 
cold and the temper will not draw, put the 
tool in and out of the fire often, until the tem- 
per shows itself, then cool off immediately. 
If the temper gets to the point of tool before 
it is polished, it will have to be heated over 
again. The above rule answers for lathe, 
plainer and shaper tools as well. 

Taps, dies, reamers and twist drills should be 
tempered in oil. After being heated to a 
cherry red all over equally, drop the tool into a 
bucket of oil (plumb) and leave it there until 
cold ; then take it out and brighten it with 
emery cloth ; be careful not to drop it, be- 
cause it is brittle and liable to break. To 
draw the temper of taps, reamers and twist 
drills, heat a heavy ring red hot and enter 
the tool centrally in the ring, so the heat will 
be equal from all sides. The hole in the ring 



— 95 — 

should be about three times the diameter of 
the tool. An old pulley hub would be about 
right. The color for reamers, taps and twist 
drills should be dark straw, turning to blue 
near the shank ; where the color is changing 
too fast, drop a little water on it ; after the 
right color is obtained, cool off in water. To 
draw the temper in dies after being cooled in 
oil, set them (the threads up) on a piece of 
red-hot iron and draw temper the same color 
as taps. 

For tempering a spring, heat it cherry red 
and put it in oil ; after it is cool, take it out 
and hold it over the fire until the oil burns 
off ; then put the spring in the oil again, then 
in the fire ; do this three times ; after the last 
time, plunge it into water and cool off. 

THE END. 




MULTIPLICATION TABLE. 



2 

4 

6 

8 

10 

12 

14 

16 

18 



1 — 

2 — 

3 — 

4 — 

5 — 

6 — 

7 — 

8 — 

9 — 



4 


X 


1 





4 


5 


X 


1 





5 


6 


X 


1 


— 6 


4 


X 


2 


— 


8 


5 


X 


2 


— 


10 


6 


X 


2 


— 12 


4 


X 


3 


— 


12 


5 


X 


3 


— 


15 


6 


X 


3 


— 18 


4 


X 


4 


— 


16 


5 


X 


4 


— 


20 


6 


X 


4 


— 24 


4 


X 


5 


— 


20 


5 


X 


5 


— 


25 





X 


5 


— 30 


4 


X 


6 


— 


24 


5 


X 


6 


— 


30 


6 


X 


6 


— 36 


4 


X 


7 


— 


28 


5 


X 


7 


— 


35 


6 


X 


7 


— 42 


4 


X 


8 


— 


32 


5 


X 


8 


— 


40 


6 


X 


8 


— 48 


4 


X 


9 


— 


36 


5 


X 


9 


— 


45 


6 


X 


9 


— 54 



7 


X 


1 


_ 


7 


8 


X 


1 


_ 


8 


9 


X 


1 


— 9 


7 


X 


2 


— 


14 


8 


X 


2 


— 


16 


9 


X 


2 


— 18 


7 


X 


3 


— 


21 


8 


X 


3 


— 


24 


9 


X 


3 


— 27 


7 


X 


4 


— 


28 


8 


X 


4 


— 


32 


9 


X 


4 


— 36 




X 


5 


— 


35 


8 


X 


5 


— 


40 


9 


X 


5 


— 45 


7 


X 





— 


42 


8 


X 


6 


— 


48 


9 


X 


6 


— 54 


7 


X 


7 


— 


49 


8 


X 


7 


— 


56 


9 


X 


7 


— 63 


7 


X 


8 


— 


56 


8 


X 


8 


— 


64 


9 


X 


S 


— 72 


7 


X 


9 


— 


63 


8 


X 


9 


— 


72 


9 


X 


9 


— 81 



CONTENTS. 



Preface , — 3 

The Boiler in General • 6 

Po Prevent and Remove Scales 27 

Pumps 29 

The Engine 40 

How to Line an Engine 48 

Valve Motion 59 

The Indicator. . . 69 

UTILES. 

To Figure a Diagram 74 

For Finding Friction 74 

For Finding H. P. of Engine, with Example. . . . 68 

For Finding Contents of Boiler 76 

For Finding Pressure on Crown Sheet 76 

For Finding Quantity of Water and Coal Used 

per Horse Power 77 

For Finding Contents of a Tank 78 

For Marking Tools 79 

For Chimneys 79 

For Babbitting Boxes 80 

To Determine Capacity of any Pump 81 

For Safe Working Pressure of Boiler 82 

For Heating Buildings 83 

For Finding Horse Power of Boiler 84 

Standard Multipliers, with Examples 75 

For Safety Valves 88 

For Figuring the Gears to Put on a Lathe 90 

Tempering Tools Used Daily 93 

Multiplication Table 96 



Just Published. 



— IN — 

Questions and Answees for Engineers, 

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Stationary Engineers' License, 

SURE. 

Price, $2 00 



ZWICKER'S mSTEUCTOE, 

The only practical work published in the United 
States giving plain and correct explanations in regard 
to Engines, Pumps, Boilers, Kemoving Scale, Valve 
Motion, Indicator, United States Standard Rules for 
Safety Valve, etc., how to figure the kind of gears 
to put on a Lathe for cutting Screws, and the Tem- 
pering of Tools used daily. 

Price, $2 00 



These are the only hooks ever published explaining 
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Engineers, Machinists and Fremen of limited educa- 
tion can understand and become expert practical 
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Send money in registered letter or P. O. order, to 

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